PM3305 Digital Storage Oscilloscope Circuits - UK Vintage Radio Repair and Restoration Discussion Forum

Chris55000 · 19th Jul 2019, 8:40 am

Hi!

I've uploaded a manual containing circuit diagrams to kO4BB for this!

If anyone runs into bother with the OQ0127 NPN transistor arrays (they're 16 pin DIL rather than the more usual 14 pin '3046 type!) there's a few here and there available from eBay, etc., but you might as well use one of those Chinese LCR-T1 testers with the colour-screen to select some discrete transistors for matched HFE from a batch of BC547s - I don't think the circuit configurations are that critical, and the pinouts are given in the Theory Of Operation Chapter 3!

Chris Williams

WME_bill · 19th Jul 2019, 5:14 pm

ON 0127. For Chris Williams,
I have found that the Philips Integrated circuit transistor array ON 0127 is the same as the Plessey SL3127 or RCA/Intersil CA3127. 5 high frequency 1.6Ghz NPN transistors, in a 16 pin package with all electrodes separate. Identical to the SL3145 / SL3086 in a 14 pin package, with two emitters common.

I have used the 14 pin versions as readily available substitutes for the16 pin variety for repairs in Telequipment and Philips scopes as almost all the citcuits use a common emitter pair. Use a 16 pin header and solder the corresponding pins from the 14 pin IC.

The original widely available version, with 0.5Ghz transistors is SL3045 / CA3045, or in ceramic pack SL3046. The CA3086 is similar.
The SL3146 (14pin) and SL3127 (16pin) is the 1.6Ghz version and SL3246 is the 3.0Ghz version.
I give the PLessey numbers, but they are commodity parts, and were also made by RCA and National as LM3046. The Intersil HFA3127 is a much improved version, with closer matching and 8Ghz Hfe.

The problem usually is to find them in anyone's list. They never seem to be agreed how to classify them. I have looked at a recent RadioSpares list which calls them transistor arrays and lists LM3046 and HFA3046 and HFA3127.

The Philips ON002 is a 4 transistor 14 pin array. So the CA3086 can be adapted.
The other frequent one is ON471 FET in Y amplifier input stages. A selected Philips BFT46.
wme_Bill.

Chris55000 · 20th Jul 2019, 5:16 pm

Hi!

Thanks for the tips Bill!

I found out the PM3055 S.M. actually quotes the CA3127 under a very similar order code as well, but your tips are a godsend!

I'm thinking about a PM3305 or PM3055 - would you recommend a Philips Digital Storage scope as a future repair project? - my only digital storage one is a 10MHz Gould OS4000 full of unobtainium and doesn't appear very promising - what is a "TY38111" for example?

Chris Williams

kevinaston1 · 20th Jul 2019, 10:48 pm

We had a Philips 400MHz digital scope at work. Fabulous beast; amazing array of measurements.

The only drawback was the power supply.

Twin SMPS units; no service data for them, and apparently, they liked to blow up on any day with a Y in it.

After getting over the shock of the price quoted for replacement power supplies, I made an external linear supply for it, connecting it to the scope with a locking multi pin plug.

It worked for many years after that, and we sold it on to someone, who never contacted us for a diagram of the supply.

Kevin

19th Jul 2019, 8:40 am	#1
Chris55000 Nonode Join Date: Aug 2007 Location: Walsall Wood, Aldridge, Walsall, UK. Posts: 2,870	PM3305 Digital Storage Oscilloscope Circuits Hi! I've uploaded a manual containing circuit diagrams to kO4BB for this! If anyone runs into bother with the OQ0127 NPN transistor arrays (they're 16 pin DIL rather than the more usual 14 pin '3046 type!) there's a few here and there available from eBay, etc., but you might as well use one of those Chinese LCR-T1 testers with the colour-screen to select some discrete transistors for matched HFE from a batch of BC547s - I don't think the circuit configurations are that critical, and the pinouts are given in the Theory Of Operation Chapter 3! Chris Williams __________________ It's an enigma, that's what it is! This thing's not fixed because it doesn't want to be fixed!

19th Jul 2019, 5:14 pm	#2
WME_bill Octode Join Date: Oct 2007 Location: Exeter, Devon, UK. Posts: 1,554	Re: PM3305 Digital Storage Oscilloscope Circuits ON 0127. For Chris Williams, I have found that the Philips Integrated circuit transistor array ON 0127 is the same as the Plessey SL3127 or RCA/Intersil CA3127. 5 high frequency 1.6Ghz NPN transistors, in a 16 pin package with all electrodes separate. Identical to the SL3145 / SL3086 in a 14 pin package, with two emitters common. I have used the 14 pin versions as readily available substitutes for the16 pin variety for repairs in Telequipment and Philips scopes as almost all the citcuits use a common emitter pair. Use a 16 pin header and solder the corresponding pins from the 14 pin IC. The original widely available version, with 0.5Ghz transistors is SL3045 / CA3045, or in ceramic pack SL3046. The CA3086 is similar. The SL3146 (14pin) and SL3127 (16pin) is the 1.6Ghz version and SL3246 is the 3.0Ghz version. I give the PLessey numbers, but they are commodity parts, and were also made by RCA and National as LM3046. The Intersil HFA3127 is a much improved version, with closer matching and 8Ghz Hfe. The problem usually is to find them in anyone's list. They never seem to be agreed how to classify them. I have looked at a recent RadioSpares list which calls them transistor arrays and lists LM3046 and HFA3046 and HFA3127. The Philips ON002 is a 4 transistor 14 pin array. So the CA3086 can be adapted. The other frequent one is ON471 FET in Y amplifier input stages. A selected Philips BFT46. wme_Bill.

20th Jul 2019, 5:16 pm	#3
Chris55000 Nonode Join Date: Aug 2007 Location: Walsall Wood, Aldridge, Walsall, UK. Posts: 2,870	Re: PM3305 Digital Storage Oscilloscope Circuits Hi! Thanks for the tips Bill! I found out the PM3055 S.M. actually quotes the CA3127 under a very similar order code as well, but your tips are a godsend! I'm thinking about a PM3305 or PM3055 - would you recommend a Philips Digital Storage scope as a future repair project? - my only digital storage one is a 10MHz Gould OS4000 full of unobtainium and doesn't appear very promising - what is a "TY38111" for example? Chris Williams __________________ It's an enigma, that's what it is! This thing's not fixed because it doesn't want to be fixed!

20th Jul 2019, 10:48 pm	#4
kevinaston1 Hexode Join Date: Aug 2014 Location: Featherstone, West Yorkshire, UK. Posts: 386	Re: PM3305 Digital Storage Oscilloscope Circuits We had a Philips 400MHz digital scope at work. Fabulous beast; amazing array of measurements. The only drawback was the power supply. Twin SMPS units; no service data for them, and apparently, they liked to blow up on any day with a Y in it. After getting over the shock of the price quoted for replacement power supplies, I made an external linear supply for it, connecting it to the scope with a locking multi pin plug. It worked for many years after that, and we sold it on to someone, who never contacted us for a diagram of the supply. Kevin